8332724: x86 MacroAssembler may over-align code

[GoeLin]

I backport this for parity with 21.0.6-oracle.

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8332724 needs maintainer approval

Issue

• JDK-8332724: x86 MacroAssembler may over-align code (Bug - P5 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/975/head:pull/975
$ git checkout pull/975

Update a local copy of the PR:
$ git checkout pull/975
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/975/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 975

View PR using the GUI difftool:
$ git pr show -t 975

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/975.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back goetz! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@GoeLin This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8332724: x86 MacroAssembler may over-align code

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been no new commits pushed to the master branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @GoeLin This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (1c21580e)

[GoeLin]

GHA failure: Well known issue with Clhsdb* tests, see also https://bugs.openjdk.org/browse/JDK-8247940. Unrelated.

[GoeLin]

/integrate

[openjdk]

Going to push as commit 3637991.
Since your change was applied there have been 5 commits pushed to the master branch:

• 2e3ef5f: 8332340: Add JavacBench as a test case for CDS
• 58cc0a2: 8321550: Update several runtime/cds tests to use vm flags or mark as flagless
• fee1d96: 8326898: NSK tests should listen on loopback addresses only
• 967a3cd: 8328303: 3 JDI tests timed out with UT enabled
• c82c70d: 8296787: Unify debug printing format of X.509 cert serial numbers

Your commit was automatically rebased without conflicts.

[openjdk]

@GoeLin Pushed as commit 3637991.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.